This invention relates to dispensers of dispensable materials and more particularly to dispensers of relatively viscous sealant materials. Still more particularly the invention relates to dispensing materials from relatively large supplies thereof, e.g., amounts of materials in the range of 5 gallons or more and weights in the range of 40 pounds.
Dispensing liquid or viscous materials such as adhesives or sealants from a supply thereof to a remote location is a fundamental part of many manufacturing operations. When the supply of the materials being dispensed is present in quantities having great bulk or weight it is important that the means for delivering the material should operate in a relatively efficient manner. Under the methods of the prior art it was usual for such materials to be dispensed from a pressurized container; however, where the air pressure required to dispense the material is great, it often happens that the pressurized air would leak past required sealant bladder seals into the dispensable material creating air bubbles therein. In cases where the dispensable material is a sealant, the air bubbles would cause the object being provided with the sealant to be rejected, greatly increasing the cost of the product. Further, once air bubbles were detected in the material, the remainder of the material would have to be scrapped which also increased the cost of the products being sealed. In a particular instance wherein the dispensable material is a sealant that is being applied to an electrical connector, the sealant (at the time of filing of this application) has a cost of $878 for 40 pounds of material and air bubbles entering the supply often caused half of the material to be unusable.
It is, therefore, an object of the invention to obviate the disadvantages of the prior art.
It is another object of the invention to enhance the dispensing of liquid or viscous materials.
It is yet another object of the invention to prevent the entrance of air bubbles into dispensed materials.
These objects are accomplished, in one aspect of the invention, by the provision of a dispenser for dispensable materials that comprises a compressible supply of the dispensable materials and a rigid holding unit having a given cross-section for containing the same. An actuator plate having the same cross-section as the rigid holding unit is positioned in the rigid holding unit. An outlet for the dispensable materials is connected to the compressible supply, and an apparatus is provided for engaging the actuator plate and applying pressure solely to the actuator plate to cause the dispensable materials to be expelled from the compressible supply. The apparatus for engaging the actuator plate and applying pressure includes a shaft and the shaft freely engages said actuator plate. By xe2x80x9cfreely engagingxe2x80x9d is meant a system wherein there is no fixed, permanent coupling between the shaft and the actuator plate so that the shaft can be subsequently retracted without disturbing the position of the actuator plate.
In a preferred embodiment of the invention the outlet for the dispensable material exits through a fitting provided in the actuator plate.